Security systems may include several sensors, such as, for example, fire alarm sensors, smoke detectors, movement sensors, glass break sensors, gate/door/window sensors, etc., which may be connected to a central base station by wires. Alternatively, the connecting wires may be replaced by a wireless communication arrangement, where each sensor is arranged as a node in a wireless communication system. Accordingly, installation costs may be reduced and certain security aspects may be enhanced.
Installation errors may occur in wireless networks due to the coordination and correlation of sensors in the system itself. In particular, it may be difficult during installation to know which sensor is (wired or wirelessly) connected to which port or which sensor has which sensor ID. While in wired systems this may be solved by physically checking the wires, in wireless systems it is different, since wireless communication channels cannot be switched off separately. If the system sends an identification request to one sensor that is mounted, for example, in office ‘A’, and a similar sensor is mounted in office ‘B’ and within (wireless) reach of the base station (i.e. its coverage area), there may be no way to find out if the sensor in office ‘A’ or ‘B’ answers this request. If due to installation errors the sensor assigned to office ‘A’ is mistakenly installed in office ‘B’ and vice versa, the system may be unable to recognize the mistake and consequently the system may be left potentially vulnerable to failure.
Every sensor and for that matter every wireless sensor node may have a unique identifier, which is part of the sensor node firmware or may even be, at least partially, hardware defined. In any case, the unique identifier, or at least parts thereof, should be accessible for the node software in order to authenticate the node when exchanging messages with the sensor network.
One way to make this identifier uniquely known to the installer is to attach a label with the identifier on the outside of the sensor case. However, there is a chance that labels may be mixed up or are simply wrong.